A press conference planned for Wednesday afternoon at 4 p.m. (5 p.m. EST) to update media on the Boston Marathon bombings has been postponed, and no new time has been scheduled, according to reports.

Citing the U.S. Attorney's office in Boston, the Boston Globe reported that the press conference, which had been pushed back earlier in the day to 4 p.m., was postponed due to activity at the Moakley federal courthouse in Boston.

CBS News also reported that the meeting would not be occurring at 4 p.m., citing the FBI.

The postponement comes after the courthouse was evacuated today following what some reporters have said was a called-in bomb threat.

The bombings Monday near the finish line of the Boston Marathon killed three and injured more than 170.